1. Field of the Invention
The present invention relates to a liquid-developing electro-photographic printer photosensitive body cleaning method and in particular, to a liquid-developing electro-photographic printer photosensitive body cleaning method for removing harmful substance (viscous substance) from a photosensitive body using an existing transfer roller cleaning mechanism without providing a new mechanism for cleaning the photosensitive body.
2. Description of the Related Art
Conventionally, in this type of liquid-developing electro-photographic printer photosensitive body cleaning method, a harmful substance (viscous substance) contained in a liquid developer adheres to a photosensitive body during printing. That is, a portion of a film-shaped developed image formed on the photosensitive body from which solvent in the liquid developer is removed is transferred onto a transfer roller together with the harmful substance by the viscous force of the liquid developer and the photosensitive body is cleaned while a portion where no film-shaped developed image is formed leaves the harmful substance on the photosensitive body.
The harmful substance is accumulated in a great amount at the portion of the photosensitive body if no film-shaped developed image is formed for several hundred pages. After this, when a film-shaped developed image is formed at that portion having the harmful substance accumulated in a great amount, this film-shaped developed image cannot be transferred onto the transfer roller because the film-shaped developed image has a great viscous force with the harmful substance, resulting in a defective image.
Moreover, the photosensitive body is contaminated by the harmful substance accumulated in a great amount and its service life is reduced. Accordingly, it is necessary to remove this harmful substance from the photosensitive body.
It is therefore an object of the present invention to provide a liquid-developing electro-photographic printer photosensitive body cleaning method for removing harmful substance (viscous substance) from a photosensitive body using an existing transfer roller cleaning mechanism without providing a new mechanism for cleaning the photosensitive body.
The liquid-developing electro-photographic printer photosensitive body cleaning method according to the present invention is for use in a liquid-developing electro-photographic printer comprising: charging means for uniformly charging a photosensitive body surface; exposure means for optically forming a latent image on the photosensitive body surface charged; developing means for developing the latent image with a liquid developer to obtain a visible developed image; drying means for drying the developed image to obtain a film-shaped developed image; transfer/fixation means for transferring the film-shaped developed image from the photosensitive body onto a transfer roller opposed to the transfer roller and transferring/fixing the transferred image onto a paper inserted into a contact portion between the transfer roller and a fixation roller; these means being arranged around the photosensitive body,
wherein a transfer roller cleaning mechanism is provided arranged in contact with the transfer roller so as to remove a harmful substance contained in a developer remaining on the transfer roller after a transfer step and deteriorating a function of the transfer roller,
the method comprising a photosensitive body cleaning mode for removing a harmful substance contained in the enveloper remaining on a printing area of the photosensitive body and deteriorating the function of the photosensitive body, the mode including:
a step of moving the fixation roller apart from the transfer roller upon completion of printing of a predetermined number of pages;
a step of forming a developed image for cleaning over an entire printing area of the photosensitive body;
a step of making the developed image for cleaning into a film shape;
a step of transferring the film-shaped developed image for cleaning onto the transfer roller; and
a step of cleaning the film-shaped developed image for cleaning using the transfer roller cleaning mechanism.
According to another aspect of the present invention, the liquid-developing electro-photographic printer photosensitive body cleaning method is for use in a liquid-developing electro-photographic printer comprising: charging means for uniformly charging a photosensitive body surface; exposure means for optically forming a latent image on the photosensitive body surface charged; developing means for developing the latent image with a liquid developer to obtain a visible developed image; drying means for drying the developed image to obtain a film-shaped developed image; transfer/fixation means for transferring the film-shaped developed image from the photosensitive body onto a transfer roller opposed to the transfer roller and transferring/fixing the transferred image onto a paper inserted into a contact portion between the transfer roller and a fixation roller; these means being arranged around the photosensitive body,
wherein a transfer roller cleaning mechanism is provided arranged in contact with the transfer roller so as to remove a harmful substance contained in a developer remaining on the transfer roller after a transfer step and deteriorating a function of the transfer roller,
the method comprising a photosensitive body cleaning mode for removing a harmful substance contained in the developer remaining on a printing area of the photosensitive body and deteriorating the function of the photosensitive body, the mode including:
a step of moving the fixation roller apart from the transfer roller upon completion of printing of a predetermined number of pages;
a step of moving the transfer roller cleaning mechanism apart from the transfer roller;
a step of forming a developed image for cleaning having a width of the printing area and a length equal to a circumference of the transfer roller on the photosensitive body;
a step of making the developed image for cleaning into a film shape and transferring the film-shaped developed image for cleaning onto the transfer roller, so that the film-shaped developed image for cleaning is adhered onto the entire surface of the transfer roller;
a step of removing harmful substance adhered to the photosensitive body by the viscous force of the film-shaped developed image for cleaning, from the photosensitive body by the transfer onto the transfer roller; and
a step of pressing the transfer roller cleaning mechanism to the transfer roller so as to remove the film-shaped developed image for cleaning and the harmful substance from the transfer roller.
According to yet another aspect of the present invention, the liquid-developing electro-photographic printer photosensitive body cleaning method is for use in a liquid-developing electro-photographic printer comprising: charging means for uniformly charging a photosensitive body surface; exposure means for optically forming a latent image on the photosensitive body surface charged; developing means for developing the latent image with a liquid developer to obtain a visible developed image; drying means for drying the developed image to obtain a film-shaped developed image; transfer/fixation means for transferring the film-shaped developed image from the photosensitive body onto a transfer roller opposed to the transfer roller and transferring/fixing the transferred image onto a paper inserted into a contact portion between the transfer roller and a fixation roller; these means being arranged around the photosensitive body,
wherein a transfer roller cleaning mechanism is provided arranged in contact with the transfer roller so as to remove a harmful substance contained in a developer remaining on the transfer roller after a transfer step and deteriorating a function of the transfer roller,
the method comprising a photosensitive body cleaning mode for removing a harmful substance contained in the developer remaining on a printing area of the photosensitive body and deteriorating the function of the photosensitive body, the mode including:
a step of moving the fixation roller apart from the transfer roller upon completion of printing of a predetermined number of pages;
a step of spraying a liquid developer solvent onto the photosensitive body between the drying means and the transfer roller so as to weaken a bondage between a harmful substance and the photosensitive body;
a step of transferring the harmful substance onto the transfer roller; and
a step of cleaning the transfer roller by the transfer roller cleaning mechanism.